Mechanical pencil with step-by-steplead feeding means



June 14, 1949. D. JUELss MECHANICAL PENCIL WITH sTEP-BY-STEP LEAD FEEDING MEANS Filed Sept. ''f 1945 Patented June 14, 1949 PATENT,.- OFF-I C E..y

This invention-1 relates to mechanical` pencils' f and; f particularlyf to improvements inf pencils i ink operation.

Pencils of'theftype describedl arerknown, the

of fwhich" aref: relatively A"complicatedand -difi- -cultito` assemble.'- Owing toff'fthe-idelicacy lof the crease -f theff cost off? production `f of fthe-f pencils.- Furthermoreg. suchf structures cannotbe`|` taken aparttrea'dily' fori cleaningand" repair.`

It i-i's zthe 2obj ect i of. the'presentiinventiorrto lprovide a 1- mechanical pencil whichfi is simple and rugged; including-1an` eifectiv'e-` mechanismz for ture and@ especiallyito' :assemble`r vision' of a'zimag-'az feeding' mechanism -rnay--be attach-edito and rernove'd from the -pencil f casingfso'#that` the operating lparts "are readily '1 accessible for cleaning: and repairfiar-1d#the*v cost of assembling'thepencil is reduced to a minimum.

Other objects" and advantages of 'the invention will be apparent: asit isbetteri.understoodfbyf reference to the following specification and accompanying drawing, in which Fig. 1 is a longitudinal section through the pencil showing the mechanismzfin Writing position;

. is afnsimlar. view of: thef-feding-funitg-;

showing the mechanism displaced to advance the lead;

Fig. 3 is a section on the line 3-3 of Fig. 1; Fig. 4 is a section on the line 4-4 of Fig. 1; Fig. 5 is a, section on the line 5-5 of Fig. 1; Fig. 6 is a section on the line 6--6 of Fig. l; Fig. '7 is an end elevation of the collet with lead-gripping members thereon; and

Fig. 8 is a section on the line 8-8 of Fig. '1. Referring to the drawing, 5 indicates a casing of suitable material, for example metal or plastic, which is generally cylindrical in form, though the cross-sectional contour may be circular, polygonal or otherwise to afford a pleasing exterior appearance. At one end, a tapered extension 6, which may also be of metal or plastic. is secured to the casing 5 in the manner hereinafter described. The extension 6 has an orifice 8 through which the lead 9 projects and is preferably provided with a tubular lead guide I0 having split fingers H at its end to frictionally engage the lead 9 and to hold it during orner-phase lori the operation-OfI the ,-lead-feedingf mechanism:-

The casing i carries within itsother'endfa:

ferrule i 21 which supports the op eratingz-A memberfi: extending rearwardly? from the pencil.'VV A cup" i ilfisienelosed" vvitliirrsthe:operating` mem-y i ber". andicarriesi an eraser I5".l By reversing` tiles operating.V member i3; :the eraser 'fmayfbe' y'made availableaforfuse:

The zmemberiflSziisfconnected :toi a sleeve I6.

which'.7 is l slid'ablyf supported withinl .the fcasings 5^ The-guideumember i1 r'ha'sf al tapered' faceffZ liz" and i ,anis openingrithrough which; theeleads are:

is disposedfbetweenean abutmentrZJin the-casing@ 5 ands the;thi-InbleaI3`A and normallyholds the.:v thimble-randa thefrsleevef firmly against f the fera ruler i-Zfa Whichi acts as.l a' stop' to limit-r. rearward;

movementzof Vthe sleeve' l They taperedextension ii is .adapted to receiveI a member 25, preferably'threadedfras-x indicated;

in the Qdrawing-f-.altl'rengh it Imayi bek connected-by f lpressdittingz':` .The .memberf' ai'oi-'ds zanzabut'. menti' aga-insti which.aiconstrictingf collar 12h having a tapered inner surface .eisadapted'ztd rest when the mechanism is in the positionfzindi-l catedi in Figi. l. f Thei collaraisamovable and' adapted. tocome to Yrest against an abutment 23': formed in fthe-taperedv extension 6. Acollet 23. extends through a .central f open-ing in; the

member 25 and .isf provided; with f a f plurality of, gripping members 30 supported on resilient arms 3l which, when the parts are in the position indicated in Fig. 1, are forced inwardly to grip the lead 3 and hold it firmly in writing position.

The other end of the collet is provided with a flange 32 and a spring 33 is disposed between the flange and the member 25. The spring 33 biases the collet to the position indicated in Fig. 1, that is, the normal Writing position.

The mechanism is assembled with the casing 5 by inserting the flange 32 in the thimble i8 and securing the parts, either by the threaded connection as shown or by frictional engagement. When the mechanism has been inserted, the pencil may be operated by depressing the operating member I3, thus actuating the sleeve i6 and causing the thimble i8 to move inwardly against the tension of the springs 23 and 33. Upon initial movement, the collar 21 is carried forwardly with the gripping members 3i) of the collet, thus advancing the lead until the collar 21 strikes the abutment 28'. Thereafter the fguidesmember i 'l which .is supcollet moves forward independently and the gripping members 30 are released from the lead. Retracting movement is effected by the action of the springs 23 and 33. As the gripping members 30 are retracted, they engage the collar 2 and carry it rearwardly until it strikes the abutment 26. Further movement of the gripping members causes them to be forced again into engagement with the lead 9 as shown in Fig. 1. During retracting movement, the lead is held by frictional engagement With the fingers il. The pencil is ready for writing and need not be actuated again until the projecting portion of the lead has been Worn down by continued use.

The magazine 22 is adapted to hold a considerable number of leads which readily enter the opening 2l and are guided thereby into the lead tube formed by the collet 29. Hence, as the lead is consumed, fresh leads enter the lead tube and are advanced at each actuation of the pencil until the leads in the magazine are exhausted. Fresh leads may be introduced by withdrawing the actuating member I3.

The structure as described has numerous advantages. number of parts, all easily manufactured. The lead feeding mechanism is assembled as a unit, it being necessary merely to first mount the spring 33 on the collet 29, slip the member 25 and the collar 21 over the gripping members 30 and introduce the latter into the recess within the tubular extension 6. The member 25 is then engaged with the tapered extension 6 by the threads or by friction. The feeding mechanism is thus .completed. It may be tested for operation before it is inserted in the casing 5. It may be separated readily from the casing for cleaning or repair. Because of the compactness of the feeding mechanisrn, it may be shorter than usual devices of this type, thus permitting a longer magazine and the use of longer leads. IIhese and other advantages distinguish the pencil as described from similar devices as heretofore known.

Various changes may be made in the form, .construction and arrangement of the parts Without departing from the invention or sacrificing the advantages thereof.

I claim:

1. In a mechanical pencil, a casing, a tapered extension secured to one end thereof, actuating means within and extending from the other end of the casing and lead feeding means operable by the actuating means and forming a unit with the It is simple, involving a minimum tapered extension, including a movable collet having leading gripping means and a restricting collar surrounding and movable within limits with the collet.

2. In a mechanical pencil, a casing, a tapered extension secured to one end thereof, actuating means within and extending from the other end of the casing and lead feeding means operable by the actuating means and forming a unit with the tapered extension, including a movable collet having lead gripping means and a restricting collar surrounding and movable within limits within the collet, and a lead guide having split fingers to hold the lead in advanced position.

3. In a mechanical pencil, a casing, actuating means in one end of the casing, a tapered extension removably secured to the other end and lead feeding means separable with the tapered extension and operable by the actuating means when the tapered extension is secured to the casing, including a movable collet having lead gripping means and a restricting collar surrounding and movable within limits with the collet.

4. In a mechanical pencil including a casing having a tapered extension at its lower end to guide and support a piece of lead, a tubular collet slidably mounted in and removable from the casing with the tapered extension and provided at one end with a plurality of spring arms having lead gripping means thereon and means at the opposite end of the casing for causing the collet alternately to grip and to release the lead whereby the lead is propelled in a step by step movement.

5. In a mechanical pencil including a casing having a tapered extension at its lower end to guide and support a piece of lead, lead feeding means supported in the tapered extension and separable therewith from the casing, including a tubular collet havin-g lead gripping means and a, restricting collar Surrounding and movable within limits with the collet and actuating means at the opposite end of the casing for the lead feeding means within the casing.

DAVID JUELSS.

REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATLNTS Nuinber Name Date 338,332 Appleby Mar. 23, 1886 2,385,329 Buchanan Sept. 25, 1945 

